“All evil is good become cancerous.”

“All normal life, Peter, consciously or otherwise, resent domination. If the domination is by an inferior, or by a supposed inferior, the resentment becomes stronger.”

“It is a mistake," he said, " to suppose that the public wants the environment protected or their lives saved and that they will be grateful to any idealist who will fight for such ends. What the public wants is their own individual comfort. We know that well enough from our experience in the environmental crisis of the twentieth century. Once it was well known that cigarettes increased the incidence of lung cancer, the obvious remedy was to stop smoking, but the desired remedy was a cigarette that did not cause cancer. When it became clear that the internal-combustion engine was polluting the atmosphere dangerously, the obvious remedy was to abandon such engines, and the desired remedy was to develop non-polluting engines.”

“Above all, never think you're not good enough. Never think that. In life people will take you at your own reckoning.”

“Individual science fiction stories may seem as trivial as ever to the blinder critics and philosophers of today, but the core of science fiction -- its essence -- has become crucial to our salvation, if we are to be saved at all.”

“We would grow tired of it, Grandpa, if it were beautiful all the time. A little change from night to night is good for us.''For you, because you're young, Wanda. You have many, many evenings ahead of you. I don't. I want more good ones.”

“The robot said, 'I have been trying, friend Julius, to understand some remarks Elijah made to me earlier. Perhaps I am beginning to, for it suddenly seems to me that the destruction of what should not be, that is, the destruction of what you people call evil, is less just and desirable than the conversion of thi sevil into what you call good.' He hesitated, then, almost as though he were surprised at his own owrds, he said, 'Go, and sin no more!”